Websites that enable users to provide reviews of service providers are common. Such reviews, however, are not very useful for a number of reasons. One such reason is that a reader of online reviews knows nothing about the author of a particular review and, thus, has no level of trust regarding the particular review. For example, because authors of online reviews are anonymous, there is no way for a reader to tell whether a positive review is written by a friend or employee of a service provider or if a negative review is written by a competitor of the service provider.
Another problem with online reviews is rooted in social influence bias. For example, a well intentioned author of a review may be influenced by other people's reviews (positive or negative), and this influence may cause the author to alter their original review in a more positive or more negative manner.
Advertising represents another issue with online review websites. For example, some online review websites permit service providers to pay to have their advertisements placed in response to user searches, thus allowing service providers to buy their way to the top of a search result. A user looking for reviews of service providers has no way of knowing that the online review website functions in this manner.